Pharmaceutical medicines and associated packaging apparatus are typically subject to relatively strict consumer protection guidelines. For example, pills, capsules, and the like, must be produced and packaged in such a way as to at least meet the minimum sterility requirements mandated by federal regulations. In addition, the pills should be delivered into the packaging such that the contents accurately meet the claimed labelling "count", i.e., each package includes exactly the predetermined number of pills. Notwithstanding the above, it is also desired to package the product in a mass production operation to offset costs typically attributed to a labor intensive operation in order to provide an economic product.
In the past, pill filling machines have been proposed which provide automated bottle counts by filling a hopper with pills and causing a plurality of the pills to be caught by a pill capturing device, such as an array of rotary slats. The rotary slats drop the captured pills into a plurality of bottles disposed in alignment with the dropping pills. The bottles are distributed along an endless conveyor belt which is timed to advance and stop the bottles according to the filling operation.
Conventional pill capturing devices more particularly include a series of rotary slats each configured to receive, hold and move a plurality of capsules or pills along a closed path. The rotary slats are typically discs fixed on a rotatable shaft and having a plurality of openings in the peripheral surface thereof for capturing individual pills. Accordingly, the closed path is arcuate and generally disposed between a pill hopper and discharge area above the conveyor belt. By the rotary action of the slat, the pills move in a direction normal to the bottle advancing automated conveyor belt. The pill capturing device then generally discharges the pills by rotating the slats which move corresponding to the closed path such that they fall out of the respective openings at the filling station. The pills are often funneled through a chute which empties into a corresponding bottle.
The count, or number of pills in the bottle, is determined by positioning the bottles in the pill dropping zone for a predetermined time. The duration of the filling operation for each bottle corresponds to the number of openings in each slat which the machine is capable of delivering to the bottles per unit of time. The duration of the filling operation, speed of the rotary slats and configuration of the pill capturing device are used to calculate the count.
U.S. Pat. No. 3,139,713 to Merrill proposes a machine with a discharge chute which is divided into a number of discharge compartments corresponding to the number of bottles being filled at the filling operation. As described, each bottle is to be filled with a count of one hundred pills. Each discharge chute receives five pills from one row or flight of the pill capturing device when the capturing device reaches a discharge position. In order to complete the filling operation, each bottle in the row receives twenty of the 5-article carrying flights.
Similarly, U.S. Pat. No. 4,674,259 to Hills proposes a series of elongated slats with cavities for carrying tablets to a set of chutes. The chutes operate with reciprocating movement to deliver the pills between first and second rows of bottles positioned at the filling station.
Unfortunately, if the pill capturing device fails to capture a pill in each and every. cavity or receptacle, or if a pill should mistakenly be diverted, at least one of the bottles can be improperly filled. The conventional solution to this problem is to situate an operator adjacent to the slats to ensure that each receptacle is filled with a pill. If a pill is missing, the operator manually places a pill in the receptacle. Such an approach involves labor costs and can be unsatisfactory for sterility purposes.
In addition, the accuracy of the count of each bottle is largely determined by the operator and, as such, a fully and consistently accurate count cannot be guaranteed. Accordingly, there is a great need for a device which provides an accurate count for each bottle but which takes advantage of the high speed and efficiency of a rotary slat apparatus.